THE ARRIVAL SEQUENCE OF THE ARTHROPOD COMPLEX FOLLOWING ATTACK BY DENDROCTONUS BREVICOMIS (COLEOPTERA: SCOLYTIDAE) IN PONDEROSA PINE

Abstract

Continuous trapping on the bark surface of Dendroctonus brevicomis LeConte infested trees in the central Sierra Nevada mountains was undertaken with the objective of determining the spatial and temporal arrival patterns of the natural enemies and other insect associates of the western pine beetle. Over 100 species of D. brevicomis associates were collected and patterns of arrival were described for many of these. The main bark beetle predators were trapped during D. brevicomis mass arrival and shortly thereafter. Enoclerus lecontei, Temnochila chlorodia, and Aulonium longum, all predaceous beetles on D. brevicomis adults and larvae, were among the first species to arrive, as was Medetera aldrichii (Diptera), a larval predator. The bark beetle parasites Roptrocerus xylophagorum and Dinotiscus (=Cecidostiba) burkei (Hymenoptera) were well synchronized with the beetles’ life cycle as they arrived late in the beetles’ larval stages when suitable hosts were available.Approximately twice as many associates were trapped in the first (spring) beetle generation as in the second (fall). Differences between species with regard to height distribution were common, and these often varied with seasonal beetle generation.Calculations of changes in species diversity through time, of the associate complex trapped at the bark surface, were made for both the first and second beetle generation. Linear correlation analysis indicated a highly significant increase in species diversity occurred from the time of the beetles’ mass arrival until brood emergence. This increase may correspond to an increase in diversity of the structure of the subcortical community, as more insect species arrived and progressively modified the habitat of the newly killed tree.

Southern Pine Beetle, Dendroctonus frontalis, Antennal and Behavioral Responses to Nonhost Leaf and Bark Volatiles

“…Suitable host trees are often unevenly distributed in forest landscapes, and inefficient host-finding behaviors can waste a beetle's limited energy reserves (Atkins, 1966;Gries et al, 1990;Kinn et al, 1994), as well as increase its risk of predation (Stephen and Dahlsten, 1976;Dahlsten, 1982) and exposure to harsh environmental conditions (McMullen and Atkins, 1962;Gries et al, 1989;Byers et al, 1998). There is an accumulating body of evidence suggesting that foraging coniferophagous bark beetles detect and avoid volatile compounds released from the leaves and/or bark of angiosperms and other nonhost taxa ('nonhost volatiles'), and thereby may improve foraging efficiency by avoiding nonhostdominated habitats and landings on unsuitable trees.…”

Influence of chemically mediated behavior on host tree colonization by four cohabiting species of bark beetles

“…The "pheromone-kairomone" designation belies the interactive nature of the matrix of interactions occurring between all cohabiting species (Birch, 1978). That this interaction matrix is far more complex than has been considered in this paper is readily apparent when it is realized that these species are only four of a large number of Scolytidae, their parasites, predators, and associated insects which arrive at pine trees during colonization (Camors and Payne, 1973;Stephen and Dahlsten, 1976). Some of these species are known to respond to olfactory stimuli from their hosts (eg: Camors and Payne, 1972;Vit6 and Williamson, 1970;Bedard and Wood, 1974).…”

Effects of Forest Type and Management on Native Wood Wasp Abundance (Hymenoptera: Siricidae) in Mississippi, United States

“…Therefore, counts of trapped S. nigricornis were standardized by converting to relative proportions (i.e., each collection day wood wasp count was divided by the total number of wood wasps captured in each trap, at each site, for each year). Relative proportions were then summed to produce cumulative proportion distributions that measured rate of capture irrespective of absolute density and were not biased by variations in time intervals between successive collection periods (Stephen & Dahlsten 1976). We summed these proportions over the entire trapping season to obtain a standardized scale of wood wasp emergence from zero to one over time (expressed as Julian date).…”